Publications by authors named "Annchen Knodt"

Psychopathy is a personality disorder characterized by affective-interpersonal features and an impulsive-antisocial lifestyle. Psychopathy commonly co-occurs with other forms of psychopathology, but current understanding of how behavioral features of psychopathy co-occur with, or are distinct from, other mental health problems is limited. In this study, we analysed data from a large sample of young adults to study the relationship between different facets of psychopathic traits and general psychopathology ("p").

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Brain structure correlates of obsessive-compulsive personality disorder (OCPD) remain poorly understood as limited OCPD assessment has precluded well-powered studies. Here, we tested whether machine learning (ML; elastic net regression, gradient boosting machines, support vector regression with linear and radial kernels) could estimate OCPD scores from personality data and whether ML-predicted scores are associated with indices of brain structure (cortical thickness and surface area and subcortical volumes). Among older adults (ns = 898-1,606) who completed multiple OCPD assessments, ML elastic net regression with Revised NEO Personality Inventory personality items as features best predicted Five-Factor Obsessive-Compulsive Inventory-Short Form (FFOCI-SF) scores, root-mean-squared error (RMSE)/SD = 0.

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To understand how aging affects functional decline and increases disease risk, it is necessary to develop accurate and reliable measures of how fast a person is aging. Epigenetic clocks measure aging but require DNA methylation data, which many studies lack. Using data from the Dunedin Study, we introduce an accurate and reliable measure for the rate of longitudinal aging derived from cross-sectional brain MRI: the Dunedin Pace of Aging Calculated from NeuroImaging or DunedinPACNI.

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Millions of adults and children are exposed to high levels of lead, a neurotoxicant, each year. Recent evidence suggests that lead exposure may precipitate neurodegeneration, particularly if the exposure occurs early or late in life, with unique alterations to the structure or function of specific subfields of the hippocampus, a region involved in memory and Alzheimer's disease. It has been proposed that specific hippocampal subfields may thus be useful biomarkers for lead-associated neurological disease.

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Brain-wide association studies (BWASs) have attempted to relate cognitive abilities with brain phenotypes, but have been challenged by issues such as predictability, test-retest reliability, and cross-cohort generalisability. To tackle these challenges, we proposed a machine-learning "stacking" approach that draws information from whole-brain magnetic resonance imaging (MRI) across different modalities, from task-fMRI contrasts and functional connectivity during tasks and rest to structural measures, into one prediction model. We benchmarked the benefits of stacking, using the Human Connectome Projects: Young Adults (n=873, 22-35 years old) and Human Connectome Projects-Aging (n=504, 35-100 years old) and the Dunedin Multidisciplinary Health and Development Study (Dunedin Study, n=754, 45 years old).

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Article Synopsis
  • * Neuroimaging reveals that many of these genetic variants have widespread effects on brain regions and are linked to various cancers and specific signaling pathways, such as p53 and Wnt.
  • * The findings suggest a connection between the genes that regulate head size and the likelihood of cancer, emphasizing the need for further research on the implications of this relationship.
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Introduction: Dementia risk may be elevated in socioeconomically disadvantaged neighborhoods. Reasons for this remain unclear, and this elevation has yet to be shown at a national population level.

Methods: We tested whether dementia was more prevalent in disadvantaged neighborhoods across the New Zealand population (N = 1.

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Biological aging is the correlated decline of multi-organ system integrity central to the etiology of many age-related diseases. A novel epigenetic measure of biological aging, DunedinPACE, is associated with cognitive dysfunction, incident dementia, and mortality. Here, we tested for associations between DunedinPACE and structural MRI phenotypes in three datasets spanning midlife to advanced age: the Dunedin Study (age=45 years), the Framingham Heart Study Offspring Cohort (mean age=63 years), and the Alzheimer's Disease Neuroimaging Initiative (mean age=75 years).

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Mapping individual differences in brain function has been hampered by poor reliability as well as limited interpretability. Leveraging patterns of brain-wide functional connectivity (FC) offers some promise in this endeavor. In particular, a macroscale principal FC gradient that recapitulates a hierarchical organization spanning molecular, cellular, and circuit level features along a sensory-to-association cortical axis has emerged as both a parsimonious and interpretable measure of individual differences in behavior.

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Biological aging is the correlated decline of multi-organ system integrity central to the etiology of many age-related diseases. A novel epigenetic measure of biological aging, DunedinPACE, is associated with cognitive dysfunction, incident dementia, and mortality. Here, we tested for associations between DunedinPACE and structural MRI phenotypes in three datasets spanning midlife to advanced age: the Dunedin Study (age=45 years), the Framingham Heart Study Offspring Cohort (mean age=63 years), and the Alzheimer's Disease Neuroimaging Initiative (mean age=75 years).

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Background: Older brain age - as estimated from structural MRI data - is known to be associated with detrimental mental and physical health outcomes in older adults. Social isolation, which has similar detrimental effects on health, may be associated with accelerated brain aging though little is known about how different trajectories of social isolation across the life course moderate this association. We examined the associations between social isolation trajectories from age 5 to age 38 and brain age assessed at age 45.

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Although higher-order cognitive and lower-order sensorimotor abilities are generally regarded as distinct and studied separately, there is evidence that they not only covary but also that this covariation increases across the lifespan. This pattern has been leveraged in clinical settings where a simple assessment of sensory or motor ability (e.g.

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Purpose: The retina has potential as a biomarker of brain health and Alzheimer's disease (AD) because it is the only part of the central nervous system which can be easily imaged and has advantages over brain imaging technologies. Few studies have compared retinal and brain measurements in a middle-aged sample. The objective of our study was to investigate whether retinal neuronal measurements were associated with structural brain measurements in a middle-aged population-based cohort.

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Although higher-order cognitive and lower-order sensorimotor abilities are generally regarded as distinct and studied separately, there is evidence that they not only covary but also that this covariation increases across the lifespan. This pattern has been leveraged in clinical settings where a simple assessment of sensory or motor ability (e.g.

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Knowledge of a person's risk for Alzheimer's disease and related dementias (ADRDs) is required to triage candidates for preventive interventions, surveillance, and treatment trials. ADRD risk indexes exist for this purpose, but each includes only a subset of known risk factors. Information missing from published indexes could improve risk prediction.

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Background: Cannabis is often characterised as a young person's drug. However, people who began consuming cannabis in the 1970s and 1980s are no longer young and some have consumed it for many years. This study tested the preregistered hypothesis that long-term cannabis users show accelerated biological ageing in midlife and poorer health preparedness, financial preparedness, and social preparedness for old age.

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Background: Cannabis legalization and use are outpacing our understanding of its long-term effects on brain and behavior, which is fundamental for effective policy and health practices. Existing studies are limited by small samples, cross-sectional measures, failure to separate long-term from recreational use, and inadequate control for other substance use. Here, we address these limitations by determining the structural brain integrity of long-term cannabis users in the Dunedin Study, a longitudinal investigation of a population-representative birth cohort followed to midlife.

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Research in adults suggests that higher peripheral inflammation is associated with increased threat-related amygdala activity and reduced cortico-amygdala connectivity. However, there is limited research in adolescents, which is striking given the major developmental changes that occur in cortico-amygdala circuitry during adolescence. In this study, we examine the association between peripheral inflammation and amygdala activity and connectivity to emotional faces in a community sample of adolescents.

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Article Synopsis
  • Past research on brain correlates of trait anger had limitations, including small sample sizes and a focus on just a few brain areas.
  • In a new study with over 1,000 young adults, researchers found that self-reported trait anger is linked to changes in brain connectivity, specifically in the supplementary motor area and right lateral frontal pole.
  • The study suggests that trait anger influences how these brain regions connect with networks involved in movement, emotions, self-awareness, and visual processing, potentially indicating its role in aggressive behaviors and mental health issues.
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Importance: Biological aging is a distinct construct from health; however, people who age quickly are more likely to experience poor health. Identifying pediatric health conditions associated with accelerated aging could help develop treatment approaches to slow midlife aging and prevent poor health in later life.

Objective: To examine the association between 4 treatable health conditions in adolescence and accelerated aging at midlife.

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Meta-analysis of functional magnetic resonance imaging (fMRI) data is an effective method for capturing the distributed patterns of brain activity supporting discrete cognitive and affective processes. One opportunity presented by the resulting meta-analysis maps (MAMs) is as a reference for better understanding the nature of individual contrast maps (ICMs) derived from specific task fMRI data. Here, we compared MAMs from 148 neuroimaging studies representing emotion categories of fear, anger, disgust, happiness and sadness with ICMs from fearful > neutral and angry > neutral faces from an independent dataset of task fMRI (n = 1263).

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Neuropsychological evidence supports the developmental taxonomy theory of antisocial behavior, suggesting that abnormal brain development distinguishes life-course-persistent from adolescence-limited antisocial behavior. Recent neuroimaging work confirmed that prospectively-measured life-course-persistent antisocial behavior is associated with differences in cortical brain structure. Whether this extends to subcortical brain structures remains uninvestigated.

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Article Synopsis
  • * The low reliability of fMRI measures can hinder their effectiveness in identifying risk and guiding interventions.
  • * Four new strategies—extended aggregation, reliability modeling, multi-echo fMRI (ME-fMRI), and improved stimulus design—are proposed to enhance the reliability and precision of fMRI measurements for clinical use.
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  • Childhood adversity is linked to long-term changes in brain structure, affecting global and regional brain integrity as measured by MRI in midlife.
  • A study involving 861 participants found that prospectively reported childhood adversity had stronger and more widespread effects on brain integrity than retrospectively reported adversity.
  • The findings suggest that the impact of childhood adversity on the brain is lasting and not confined to specific areas, indicating a broad biological imprint of early life experiences.
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Disappointing results from clinical trials designed to delay structural brain decline and the accompanying increase in risk for dementia in older adults have precipitated a shift in testing promising interventions from late in life toward midlife before irreversible damage has accumulated. This shift, however, requires targeting midlife biomarkers that are associated with clinical changes manifesting only in late life. Here we explored possible links between one putative biomarker, distributed integrity of brain white matter, and two intervention targets, cardiovascular fitness and healthy lifestyle behaviors, in midlife.

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